Magnetic bubble, "field-access" memories are now well known in the art. A characteristic of such a bubble memory is the pair of coils which provides a magnetic field which reorients (typically rotates) in the plane of the material (chip) in which the magnetic bubbles move. The bubble memory chip is encompassed by the field generating coils. Therefore, provision must be made to interconnect electrical conductors defined on the surface of the chip to drivers external to the coils. Since these coils are disposed orthogonally with respect to one another, one fits within the other in the most practical arrangements to date. Since the power required to drive the coils increases as does the size of the coils, the coils are kept as small as possible, and they fit together rather closely. Therefore, space allocated for the passage of electrical conductors through the coils is increased at the expense of increased power requirements and it is advantageous to maintain that space small.
Moreover, heat dissipated in the volume encompassed by the coils is advantageously removed by provision of a heat conduction path through the coils. This too is provided at the expense of an increase in the size of the coils and thus an increase in power.